Double belt drawing mechanism for textile machines



Dec 15, 1953 KARL-HANS NEU 2,662,249

DOUBLE BELT DRAWING MECHANISM FOR TEXTILE MACHINES Filed Nov. 29, 1952 3 Sheets-Sheet 1 756 wry/m9:

KARL- HANS BY! Dec. 15, 1953 KARL-HANS NEU 2,662,249

DOUBLE BELT DRAWING MECHANISM FOR TEXTILE MACHINES Filed Nov. 29, 1952 s Sheets-Sheet 2 7g, 55 76 75 F763 w 'z i v w il 1 L 1 g l :43:

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K Hmvs NEu Dec. 15, 1953 KARL-HANS N 2,662,249

DOUBLE BELT DRAWING MECHANISM FOR TEXTILE MACHINES Filed Nov. 29, 1952 3 Sheets-Sheet 3 l/IKEWIM I KARL- HANS Ihzu Patented Dec. 15, 1953 DOUBLE BELT DRAWING MECHANISM FOR TEXTILE MACHINES Karl-Hans Neu, Stuttgart, Germany Application November 29, 1952, Serial No. 323,291

Claims priority, application Germany November 30, 1951 7 Claims. 1

The present invention relates to textile machines and more particularly to double belt drawing mechanisms of spinning machines; These drawing mechanisms generally have a turnable top member for holding pressure rolls, this top member, in its operating position, extending at least partly over the drawing mechanism.

There are known double belt drawing mechanisms of" this type where the top belts and their holders may be independently turned upwardly away from an operating position. Top belt holders of this type are, for example, releasablylocked to a bottom belt arrangement of the drawing mechanism and can be individually unlocked and then turned upwardly. These known ar rangements, which require an independently turnable support for the top rolls and an independently turnable holder for the top belts of the drawing mechanisms, are very inconvenient to operate.

One of the objects of the present invention is to improve apparatus of the above type by providing a means for automatically separating the top belt membersfrom the bottom belts of the drawing mechanism upon turning of the top rolls holder upwardly.

A further object of thepresent invention is to provide a means for releasably locking the top belt holder of the drawing mechanism in a predetermined operating position,

A still further object ofthe present invention is to provide a releasable locking means for the topbelt holder which is automatically released and engaged upon movement of the top rolls holder from and to its operating position, respectively.

An additional object of the present invention is to provide a means for releasably locking the top belt holder to'a part oithe bottom belt holder.

Another object of the present invention is to provide guides for the top belts-f the drawing mechanism which also guide the bottom belts of the drawing mechanism.

Still another object of the present invention is to provide a meansfor adjusting the operating position in which the holder for the top belts of the drawing mechanism is releasably locked.

Yet another object of'the present invention is to provide a means for automatically limiting turning of the top belt holder with respect to the support for the top rolls.

A still additional object of the present inven tion is to provide ameansfor utilizing the stiffnessof' the top belts of the drawing mechanism for maintaining: the top belt holder and guidingv 2 apparatus in a predetermined operating position.

With the above objects'in View, the present inventionmainly consists of a double belt drawing mechanism which includes a base means on which a bottom roll means is turnably mounted for rotation. about its axis. A bottom belt means engages the bottom roll means and extends forwardly therefrom, and a guide rail is fixed to the base means, is located forwardly from the axis of the bottom roll. means, is parallel to this axis, and engages the bottom belt means to guide the latter, this guide rail having a rear side facing the bottom roll means. A support means is turnably connected to the base means for movement downwardly to and upwardly away from an operating position where the support means is located over the base means. A top roll means is turnably carried for rotation about its axis by the support means and is movable with the latter, this top roll means being located over the bottom roll means and having a spindle parallel to the axis of the bottom roll means. A top belt means engages the top roll means and the bottom belt means and extends forwardly from the top roll means. mounted at an intermediate portion thereof on the spindle of the top roll means for guiding the top belt means, this guide means including a front end portion fixed to the intermediate portion thereof, located in front of the top roll means and engaging the top belt means. The guide means also includes a rear end portion located to the rear of the top roll means for engaging the support means to limit turning movement of the guide means and the top belt means therewith about the spindle of the top roll means when the support means is turned upwardly away from the base means. Also, the guide means includes at least one downwardly extending hook portion located adjacent the rear side of the guide rail of the bottom belt means for releasably holding the guide means of the topbelt means in a predeterminedoperating position.

The novel features which are considered as characteristic for the invention are set forth in particular in' the appended claims. The invention itself, however, both as to its construction and" its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specifie embodiments when read in connection with the accompanying drawings, in which:

Fig. I is a fragmentary, side, partly sectional A guide means is turnablyview of a drawing mechanism constructed in accordance with the present invention;

Fig. 2 is a fragmentary, sectional view taken along line 11-11 of Fig. 3 in the direction of the arrows and illustrating a part of the structure of Fig. 1 on an enlarged scale;

Fig. 3 is a fragmentary, top plan view of the structure of Fig. 2, with some parts being cut away to clearly illustrate the structure of the invention;

Fig. 4 is a perspective view of a part of the structure shown in Figs. 1-3;

Fig. 5 is a fragmentary, partly sectional, side view, corresponding to Fig. 2, of a different embodiment of the invention; and

Fig. 6 is a perspective view of a part of the structure of Fig. 5.

Referring now to the drawings, there is shown in Fig. 1 a schematic illustration of a double belt drawing mechanism including a construction corresponding to that embodiment of the invention which is illustrated in Figs. 2-4 of the drawings.

On the known base structure Hi, there are turnably mounted the pairs of bottom rolls II, l2, and I3. A bottom belt 28 is guided about the bottom rolls l2, and a guide rail M is fixed to the base II] in a known way to guide the pair of bottom belts 28, one of which is shown in Fig. l. A tensioning roller l5, of any known construction, bears against the lower part of each of the bottom belts 28 to tension the same. The top rolls I6, I 1 and I8 are carried by guide arms !9, 20 and 2|, respectively, in a known way, and are resiliently urged downwardly toward the drawing plane. These guide arms are resiliently mounted on the elongated support 22 for the top roll structure, as is clearly shown for the central guide arm 20 in Fig. 1, where it is apparent that the spring 24 bears against the guide arm 20 to urge the latter in a counterclockwise direction about the pivot pin 23 on which it turns.

A bar 26 is fixed to the base Ill, and a bracket 21 is fixed to the bar 26 through the medium of a bolt and nut means 25 which draws together opposite parts of a split portion of the bracket 21. The support 22, for the top rolls, is pivoted on the bracket 21 by the pivot pin 28 carried by the bracket 21, so that the support 22 is turnable upwardly from and downwardly toward the operating position illustrated in Fig. 1. The support 22 is releasably locked in its operating position by the lock structure 29 which is well known and forms no part of the present invention. The support 22 is provided with a stop 22! which engages the bracket 2! to limit the turning movement of the support 22 in a direction away from its operating position shown in Fig. 1. The pair of top belts of the double belt drawing mechanism are guided over the central pair of to rolls I! of Fig. 1, and the details of this construction are illustrated in Figs. 2-4.

In the two embodiments of the inventions which are respectively illustrated in Figs. 2-4 and Figs. 5 and 6, the drawing plane is shown as extending horizontally only for the sake of clarity, and it is to be understood that the drawing plane actually is inclined downwardly as shown in Fig. 1.

In Fig. 2, the central part of the top roll support 3| is fragmentarily and schematically shown. The guide arm 32, corresponding to the guide arm 20 of Fig. l, is turnable on the pivot pin 33 which is rigidly fixed to the support 3!, and the spring 24 urges the arm 32 downwardly, the sup- 4 port 3! being provided with fingers 3| to limit the movement of the arm 32 under the influence of spring 25 when the support 31 is raised upwardly away from its operative position.

The arm 32 is provided with downwardly bent side portions, at the left end thereof as viewed in Fig. 2, and these downwardly bent side portions are each provided with a U-shaped recess in which the spindle 35 of the top rolls 36 is located so that the left end portion of the guide arm 32 forms a saddle-like connection with the spindle 35. The downwardly extending side portions of the arm 32 are provided with inwardly extending projections 32! on which a leaf spring 3 5 having the shape shown in Fig. 2 is mounted so as to engage the spindle 35 and hold the latter on the guide arm 32 for upward and downward movement therewith. The top rolls 35 are in this way turnably connected to the guide arm 32.

The pair of lower belts 28 are guided over the bottom rolls l2 and the guide rail 83 in the same way as was discussed above in connection with Fig. 1. The tensioning rolls [5 are omitted from Fig. 2 and the remaining figures of the drawings.

The top belts 15 of the double belt drawing mechanism are guided by a guide means illustrated in detail in Fig. 4. This guide means is provided with a pair of side plates for laterally guiding each of the belts '15, so that there are two of these side plates 16 provided for each belt 15. The side plates 16 are provided with U-shaped recesses ml in which the spindle 35 is located and with forward extensions 164 which are formed with notches in which the guide rail 19 is fixedly located, this guide rail 19 being common to both of the top belts l5 and having bent ends 191 for properly locating the same on the plates 16. The guide rail 79 may be welded or soldered to the side plates 16. The central pair of guide plates 16 are held together by the strip I55 fixedly connected thereto or formed integrally therewith. The forward extensions 764 of the side plates 16 are formed at their lower end portions with the hook shaped parts 166 which releasably engage one side of the angle member 85 which is screwed to the guide rail 33 by the screw members 86, as is clearly shown in Fig. 2.

During operation, the stiffness of the top belts i5 urge the above-described guide means upwardly by engagement with the lower edge of member 19, but this upward movement is prevented by the cooperation of the hook members with the bar 85 so that the top belts respectively press against the bottom belts and provide the required pressure in the drawing plane.

Upon upward turning movement of the support 3| from the operative position thereof, the pair of top rolls 36 are carried upwardly therewith, as was described above. The top belt guide means thus tends to turn in a counterclockwise direction about spindle 35, as viewed in Fig. 2, because of the engagement between the hook portions 166 and the angle bar 85. Upon further upward turning of the support 3 I, the hook members automatically slide over the angle bar 85 to automatically release the top belt guide from the guide rail 83. During the continued upward turning movement of the support IN the top belt guide means continues to turn in a counterclockwise direction about spindle 35, as viewed in Fig. 2, by gravity, until the rear strip 565 engages the guide arm 32.

Upon downward movement of the top roll support 31 back to its operating position, the parts of the top belts 15 which engage the bar 19 first as contact thelower. belts 28i mover forwardly? along the: latter. until the; top: roll support is again in its operating position. Simultaneously with; this movement of; the top roll mechanism to. the position shown inFig; 2, the: hook portions 166- become automatically engaged with the angle bar. 85: so. as. to again releasably and automatically lock the top belt guide means in its operative; position.

Figs. 5 and 6 show a. different embodiment: of; the invention. which includes a. support: 31' for the top rolls, a guide arm 32, a pivot" pin 33, a spring 24, fingers 31", projections 32],. and aleaf; spring 34, identical with the same elements of. the; em.- bodiment of Fig. 2, the: top rolls: 35; being carried; by this structure. in the same way as; was. described above.

The bottom belts 28. areguided over thebottom rolls l2' and a guide rail 4-]. in exactlythezsame way as described above. It: will be noted, how-- ever, that the guide rail 4! is freeof any additional elements such as angle bars and the like.

The guide means for the' pair of top belts 48' isshown in detail in Fig; 6, from which it is appar'-- cut that a front plate 42 is provided-with a forward curved edge 421 for guiding the top belts, this front plate 42 being connected to the two outermost side plates 44 and the two inner side platesd3' by any suitable means such as-welding, soldering, or the like. The outer side plates Mr are provided with cars 44-! which are joined to the plate 42, and the inner side plates 4-3 are provided with ears 43| which are-joined to the:front plate 42. The two inner plates 43" are inter-- connected by cross rod. 45' and: are formedwith U-shaped recesses 432,, respectively, iniwhichthexspindle 35 is located. The outerside plates 44:

simply-are located respectively opposite; the ends.-

of the spindle 35;.

The front plate 42 extends. across both of the top belts 48 and the curved front edge 42:! thereof is bent backwardly upon itself to form the sub:- stantially V-shaped part 422. In its central portion, the plate 42 is provided. with. adownwardly struck part 423- formed with an elongated slot;

4424. A look member 4t is located against this. part 423, on the front side thereof, and is threadedly connected to the screwmember. 41? which has:

a head larger than theslot424 soasto adjusteblyclamp the lock member 48.- to the portion423f of. the front plate. A12. the lock member at is bent, forwardly" so: as'tu extend beneath the guide rail 4 i. The-side plates.

as and 44- are made sufiiciently-large to engage-.- theside edges of the top belts-48 so as to;latera'lly guide the latter.

The structure-of Figsp andzfi operates inmuch. the sameway as the structure of Figs; 2-4. The. lower end 4 of lock 46 engages the guiderail 4| toprevent upward turning of theguide means.

as a result of the stiffness of the top belts 48; When the support 3! is turned upwardly; the lower end Q6! of the lock member 45' engages the rail 4% to cause the top belt mechanism to turn in a counterclockwise direction about spindle 3.5:,- as viewed in Fig. 5, the lower end. 46! of the; lock 46 automatically sliding across the guide: rail 4!, and the top belt mechanism further turning in the same direction by gravity until the cross rod :25 engages the arm32.

When the top roll support 31 is movedbaclc to its operative position, the forward lower. ends of the top belts Q8 first engage. thebottom belts: 28 and move forwardly along the. latter so. that the lower end GM ofithe lock 46? automatically The lower free end 4161i of 1-. scribed. embodiments: of. the invention", it is: a

verysimple: matter toguidethe bottom belts 28 with the: same structure which. guides the top: belts. Thus, in the embodiment of Figs. 2-4, the lower extensions of the side plates 'lt enga'ge the t side edges ofLthe bottom belts 28 to laterally guide the latter and with the embodimentofFigs- 5 and 6, lowerextensions of the plates 43 and 44 may be provided for this same purpose,- or suit able guide members may be connected to the frontplate #2 for thispurpose;

It. will be understood that each of the ere ments' described above, or two or more togethen. may also. find a usefulapplication in other types of double belt drawing mechanisms for textile machinesdiffering from the types described above.

While the invention has been illustratedand described as embodiedin guide means: for top belts of double belt drawing mechanismsfortextile machines, it.is not intended to be limit'edte the details shown, since various modifications and structural changesmay be madewithout departing in any way fromthe spirit ofthepresent invention.

Without further analysis; the foregoing will so fully reveal the gist of the present inventionthat others can by applying currentknowledge readily adapt it for various applications'without omitting features that, from. the standpoint" of prior art, fairly-constitute essential, charac= teristics of the generic or'specific'aspects of this" invention and, therefore, such adaptations should". and are intended tobecomprehended within the meaning and'range ofequivalence of thefollowing claims.

What is claimed as new and. desired to. be securedby Letters Patent is:

l.,In a. double belt drawing mechanism fortextile machines, in combination, base means;

bottomrollv means turnably mounted for: rota.-

tion about its axis. on said base means; bottom belt. means engagingsaid bottom roll meansand extending forwardly therefrom; a guide. rail-fixed. to said base means, being located forwardlyfrom.

J said axis ofsaid; bottom rollmeans, being. parallel to said axis, and engaging said bottom belt means. to guide. the. latter, said guide rail having a rear side facing said bottom roll means; support means. turnably connected to said base 'means for movement downwardly to and upwardly away froman operatingposition where. said support. means, is. located over said. base means; top roll means turnably carried for. rotation. about its axis by said support means. and.

I being movable with the latter, said top roll means being located over said bottom. roll means and having, a spindle parallel to'the axis of saidbottom roll means; top belt means. engaging. said. top roll mean-sand. saidbottom beltmeansand.

' extending forwardly from. said top roll. means;

and" guide means turnably mounted. at an intermediate portion thereofon said, spindle. ofsaid top roll means for guiding said. top belt means, said' guide means including a front. endportionfixed to said intermediate portionthereofllocatr ed'in front" of" said top roll' means and engaging. said top belt means; and a rear end portionlocated to the rear of said; top roll means. for engaging said: support means to limit. turning movement of said guide means and'saicr top'beIt' means therewith about said spindle of said top roll means when said support means is turned upwardly away from said base means, and said guide means including at least one downwardly extending hook portion located adjacent said rear side of guide rail for releasably holding said guide means in a predetermined operating position.

2. In a double belt drawing mechanism for textile machines, in combination, base means; bottom roll means turnably mounted for rotation about its axis on said base means; bottom belt means engaging said bottom roll means and extending forwardly therefrom; a guide rail fixed to said base means, being located forwardly from said axis of said bottom roll means, being parallel to said axis, and engaging said bottom belt means to guide the latter, said guide rail having a rear side facing said bottom roll means; support means turnably connected to said base means for movement downwardly to and upwardly away from an operating position where said support means is located over said base means; top roll means turnably carried for rotation about its axis by said support means and being movable with the latter, said top roll means being located over said bottom roll means and having a spindle parallel to the axis of said bottom roll means; top belt means engaging said top roll means and said bottom belt means and extending forwardly from said top roll means; guide means turnably mounted at an intermediate portion thereof on said spindle of said top roll means for guiding said top belt means, said guide means including a front end portion fixed to said intermediate portion thereof, located in front of said top roll means and engaging said top belt means, and a rear end portion located to the rear of said top roll means for engaging said support means to limit turning movement of said guide means and said top belt means therewith about said spindle of said top roll means when said support means is turned upwardly away from said base means, and said guide means including at least one downwardly extending hook portion located adjacent said rear side of guide rail for releasably holding said guide means in a predetermined operating position; and a catch member fixed to said rear side of said guide rail and releasably engaging said hook portion of said guide means.

3. In a double belt drawing mechanism for textile machines, in combination, base means; bottom roll means turnably mounted for rotation about its axis on said base means; bottom belt means engaging said bottom roll means and extending forwardly therefrom; a guide rail fixed to said base means, being located forwardly from said axis of said bottom roll means, being parallel to said axis, and engaging said bottom belt means to guide the latter, said guide rail having a rear side facing said bottom roll means; support means turnably connected to said base means for movement downwardly to and upwardly away from an operating position where said support means is located over said base means; top roll means turnably carried for rotation about its axis by said support means and being movable with the latter, said top roll means being located over said bottom roll means and having a spindle parallel to the axis of said bottom roll means; top belt means engaging said top roll means and said bottom belt means and extending forwardly from said top roll means; and guide means turnably mounted at an intermediate portion thereof on said spindle of said top roll means for guiding said top belt means, said guide means including a front end portion fixed to said intermediate portion thereof, located in front of said top roll means and engaging said top belt means, and a rear end portion located to the rear of said top roll means for engaging said support means to limit turning movement of said guide means and said top belt means therewith about said spindle of said top roll means when said support means is turned upwardly away from said base means, and said guide means including at least one downwardly extending hook portion located adjacent said rear side of guide rail for releasably holding said guide means in a predetermined operating position, said hook portion being adjustably connected to said guide means.

4. In a double belt drawing mechanism for textile machines, in combination, base means; bottom roll means turnably mounted for rotation about is axis on said base means; bottom belt means engaging said bottom roll means and extending forwardly therefrom; a guide rail fixed to said base means, being located forwardly from said axis of said bottom roll means, being parallel to said axis, and engagaing said bottom belt means to guide the latter, said guide rail having a rear side facing said bottom roll means; support means turnably connected to said base means for movement downwardly to and upwardly away from an operating position where said support means is located over said base means; top roll means turnably carried for rotation about its axis by said support means and being movable with the latter, said top roll means being located over said bottom roll means and having a spindle parallel to the axis of said bottom roll means; top belt means engaging said top roll means and said bottom belt means and extending forwardly from said top roll means; and guide means turnably mounted at an intermediate portion thereof on said spindle of said top roll means for guiding said top belt means, said guide means including a front end portion fixed to said intermediate portion thereof, located in front of said top roll means and engaging said top belt means, and a rear end portion located to the rear of said top roll means for engaging said support means to limit turning movement of said guide means and said top belt means therewith about said spindle of said top roll means when said support means is turned upwardly away from said base means, and. said guide means including at least one downwardly extending hook portion located adjacent said rear side of guide rail for releasably holding said guide means in a predetermined operating position, said hook portion being adjustably connected to said guide means and having a free end portion located beneath the bottom of said guide rail when said guide means is in said predetermined operating position.

5. In a double belt drawing mechanism for textile machines, in combination, base means; bottom roll means turnably mounted for rotation about its axis on said base means; bottom belt means engaging said bottom roll means and extending forwardly therefrom; a guide rail fixed to said base means, being located forwardly from said axis of said bottom roll means, being parallel to said axis, and engaging said bottom belt means to guide the latter, said guide rail having a rear side facing said bottom roll means; support means turnably connected to said base means for move- ,ment downwardly to and upwardly away from an operating position where said support means is located over said base means; top roll means turnably carried for rotation about its axis by said support means and being movable with the latter, said top roll means being located over said bottom roll means and having a spindle parallel to the axis of said bottom roll means; top belt means engaging said top roll means and said bot tom belt means and extending forwardly from said top roll means; a pair of parallel side plates located in planes normal to the drawing plane and each being formed with a U-shaped recess extending upwardly from a bottom edge thereof and in which said spindle of said top roll means is located, each of said side plates having a downwardly extending free hook portion at the lowest part thereof; a front plate fixed to said side plates at the front ends thereof and having a front edge engaging said top belt means; a connecting member fixed to and interconnecting said side plates and being located to the rear of said top roll means to engage said support means and limit turning of said side plates on said spindle of said top roll means when said support means is turned upwardly away from said base means; and catch means fixed to said guide rail at said rear side thereof and releasably engaging said hook portions of said side plates to hold the latter in a predetermined operating position, said hook portions automatically sliding 01f from and onto said catch means when said support means is respectively moved upwardly away from and downwardly to said operating position thereof.

6. In a double belt drawing mechanism for textile machines, in combination, base means; bottom roll means turnably mounted for rotation about its axis on said base means; bottom beltmeans engaging said bottom roll means and extending forwardly therefrom; a guide rail fixed to said base means, being located forwardly from said axis of said bottom roll means, being parallel to said axis, and engaging said bottom belt means to guide the latter, said guide rail having a rear side facing said bottom roll means; support means turnably connected to said base means for movement downwardly to and upwardly away from an operating position where said support means is located over said base means; top roll means turnably carried for rotation about its axis by said support means and being movable with the latter, said top roll means being located over said bottom roll means and having a spindle parallel to the axis of said bottom roll means; top belt means engaging said top roll means and said bottom belt means and extending forwardly from said top roll means; a pair of parallel side plates located in planes normal to the drawing plane and each being formed with a U-shaped recess extending upwardly from a bottom edge thereof and in which said spindle of said top roll means is located; a front plate fixed to said side plates at the front ends thereof, extending forwardly therefrom, and having a front end engaging said top belt means, said front plate including an intermediate portion extending downwardly toward said guide rail; a connecting member fixed to and interconnecting said side plates and being located to the rear of said top roll means to engage said support means and limit turning of said side P plates on said spindle of said top roll means when said support means is turned upwardly away from said base means; and a hook member 10 adjustably connected to said intermediate portion of said front plate and extending downwardly across said rear side of said guide rail and beneath the latter to releasably maintain said front and side plates in a predetermined operating position, said hook member automatically sliding off from and back to said guide rail when said support means is respectively moved upwardly away from and downwardly to said operating position thereof.

7. In a double belt drawing mechanism for textile machines, in combination, base means; bottom roll means turnably mounted for rotation about its axis on said base means; bottom belt means engaging said bottom roll means and extending forwardly therefrom; a guide rail fixed to said base means, being located forwardly from said axis of said bottom roll means, being parallel to said axis, and engaging said bottom belt means to guide the latter, said guide rail having a rear side facing said bottom roll means; support means turnably connected to said base means for movement downwardly to and upwardly away from an operating position where said support means is located over said base means; top roll means turnably carried for rotation about its axis by said support means and being movable with the latter, said top roll means being located over said bottom roll means and having a spindle parallel to the axis of said bottom roll means; top belt means engaging said top roll means and said bottom belt means and extending forwardly from said top roll means: a pair of parallel side plates located in planes normal to the drawing plane and each being formed with a U-shaped recess extending upwardly from a bottom edge thereof and in which said spindle of said top roll means is located; a front plate fixed to said side plates at the front ends thereof, extending forwardly therefrom, and having a front end engaging said top belt means, said front plate including an intermediate portion extending downwardly toward said guide rail and being formed with a slot passing therethrough and also extending toward said guide rail; a connecting member fixed to and interconnecting said side plates and being located to the rear of said top roll means to engage said support means and limit turning of said side plates on said spindle of said top roll means when said support means is turned upwardly away from said base means; a screw member extending through said slot of said intermediate portion of said front plate and having a head engaging said intermediate portion on one side thereof; and a hook member threadedly connected to said screw member and engaging said intermediate portion of said front plate on the side thereof opposite to said head of said screw member so that said hook member is thereby adjustably connected to said intermediate portion of said front plate, said hook member extending downwardly across said rear side of said guide rail and beneath the latter to releasably maintain said front and side plates in a predetermined operating position and said hook member automatically sliding oif from and back to said guide rail when said support means is respectively moved upwardly away from and downwardly to said operating position thereof.

KARL-HANS NEU.

No references cited. 

